Evolution of Showy Traits

This is a picture of a male black grouse taken from your text; females don't have the elaborate tail plumes of the males which seem to have no other function than to attract females. This species exhibits lek polygyny.

A. Name the specific process that has resulted in sexual dimorphism in this species.

B. Name and describe two of the three hypotheses we have for why showy traits like the males' tail plumes have evolved.

C. The text indicates that the "hotshot" hypothesis best accounts for the evolution of lek polygyny in this species. What are the basics of this hypothesis.

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In this question we are looking at the black grouse.

a. The sexual dimorphism (different appearance of the genders) is due to a natural selection process.

b. The theories to explain this dimorphism include: sexual selection, ecological selection and natural selection. Sexual selection occurs when one gender is limiting. If females are limiting they can ...

Solution Summary

This solution discusses the showy trait in a male grouse in 184 words. The expert names and describes two of the three hypotheses we have for why showy traits like the male's' tail plumes have evolved.